For better or worse, it’s next to impossible to successfully modify the Constitution without significant support. It has to be ratified by about 38 States (3/4 of the State legislatures or 3/4 of the conventions called in each State). That’s after either 2/3 of both Houses of Congress (2/3 of the House of Representatives and 2/3 of the Senate) propose an amendment or 2/3 of the State legislatures request one via a convention.
In a way, it’s a good thing since it keeps the Constitution from being able to be changed on a whim, and it mostly keeps it from being affected by the political tug-of-war that happens every few years in the US.
It’s also a bad thing, though, as it makes it very difficult to adapt to certain situations that wouldn’t have happened 200+ years ago.